1. Technical Field
The present invention relates generally to a window covering, and more particularly to a cutting machine for cutting rails and window covering material of a window covering.
2. Description of Related Art
Typically, there are a variety of sizes of windows, so the manufactures sell the window coverings to retailers, and the retailers cut the window covering to fit a specific window. A conventional cutting machine for cutting a window covering is taught in U.S. Pat. No. 6,435,066 (hereafter the '066 patent), titled “Cutting apparatus for window covering and methods therefor”, which provides a cutting device on a machine base to cut the window covering.
The '066 patent teaches that a blade, which is used to cut the window coverings, has to simultaneously touch the headrail, the bottom rail, and the window covering material before cutting. However, when the cutting machine of the '066 patent is used to cut a blind with a cellular shade or slats, it would have an uneven cutting result when the blinds are not pressed enough. Therefore, the key to have a nice cutting result is how to firmly press the blinds. However, the clamping device of the '066 patent can't provide sufficient clamping force. On the contrary, if power of the clamping device is too large, it might damage some slats of the blinds.
Furthermore, the '066 patent teaches that the blade simultaneously touches the headrail, the bottom rail, and the window covering material before cutting. It makes the user have to exert a large strength to cut the window coverings, and sometime it will damage the elements with such large strength. Beside, the '066 patent provides a rigid machine base to sustain the window coverings that would damage the blade after the blade cutting the window coverings several times, and that is bad to the afterwards cutting tasks.